v3.26.1
Cover
Jun. 25, 2026
Document Type 8-K
Amendment Flag false
Document Period End Date Jun. 25, 2026
Entity File Number 001-42514
Entity Registrant Name Archimedes Tech SPAC Partners II Co.
Entity Central Index Key 0002028516
Entity Tax Identification Number 00-0000000
Entity Incorporation, State or Country Code E9
Entity Address, Address Line One 2093 Philadelphia Pike #1968
Entity Address, City or Town Claymont
Entity Address, State or Province DE
Entity Address, Postal Zip Code 19703
City Area Code 725
Local Phone Number 312-2430
Written Communications true
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company true
Elected Not To Use the Extended Transition Period false
Units [Member]  
Title of 12(b) Security Units, each consisting of one Ordinary Share, par value $0.0001 per share, and one-half of one redeemable Warrant
Trading Symbol ATIIU
Security Exchange Name NASDAQ
Ordinary Shares  
Title of 12(b) Security Ordinary Shares
Trading Symbol ATII
Security Exchange Name NASDAQ
Warrants  
Title of 12(b) Security Warrants
Trading Symbol ATIIW
Security Exchange Name NASDAQ